Ground pin



FIG. 1 is a top plan view of a ground pin embodying the design;

FIG. 2 is a bottom plan view thereof;

FIG. 3 is a side view thereof, all other sides being the same;

FIG. 4 is a top perspective view thereof; and,

FIG. 5 is a bottom perspective view thereof. 

CLAIM I claim the ornamental design for a ground pin, as shown and described. 